A cartoon depiction of the one-dimensional carbon budget for the upper water column of the ASP. Major carbon inventories include dissolved inorganic carbon (DIC), particulate organic carbon (POC), dissolved organic carbon (DOC), and mesozooplankton (Mesozoop). Microbial biomass, including phytoplankton, microzooplankton (Microzoop), particle-associated (PA) and free-living (FL) bacteria (Bact) are distributed into the major carbon inventories. Exchanges between the inventories include net primary production (NPP), microbial respiration, zooplankton respiration (Zoop Resp), grazing (Gr), bacterial carbon demand (BCD), aggregation (AGG), and fecal pellet production (FEC). Additions to or losses from the upper water column occur through gas exchange and export.